Daphne Caruana Galizia in April 2016. She died last month in a powerful car bomb yards from her home.
Photograph: Jon Borg/AP

MEPs on a fact-finding mission to Malta after the killing of the investigative journalist Daphne Caruana Galizia have said they arrived “seriously concerned” about the rule of law on the island and were leaving “even more worried”.

The Portuguese Socialist MEP Ana Gomes said the delegation found it “extremely disturbing” that some of the officials it met did not answer its questions. One, prime minister Joseph Muscat’s chief of staff, Keith Schembri, read out a prepared statement, she said, while another “never showed up”.

The German Green MEP Sven Giegold said after two days of meetings with government officials, regulators, local journalists media and civil rights activists that he was particularly concerned about the island’s police and attorney general.

Both had demonstrated “a high degree of unwillingness to investigate and a failure to prosecute corruption and money-laundering”, Giegold said, adding he left a meeting with senior police officials with an impression of “incompetence”.

Giegold said publicly available information and even reports by the anti-money laundering agency FIAU had failed to trigger investigations, “protecting high government officials and financial institutions”.

Malta’s judicial system “has demonstrated systemic problems rooted in Malta’s constitution”, he said, adding that the prime minister’s right to appoint top officials had severely weakened the judicial system and financial supervision.

Her family are taking legal action against the island’s police, saying the investigation into the killing cannot be impartial and independent since it is being run by a senior officer married to a top government minister who was the subject of critical articles by Caruana Galizia.

The MEPs’ delegation would now submit its report and recommendations, Giegold said, and pursue “continued dialogue with the European commission in the run-up to an article 7 procedure”, a formal audit of the rule of law in a member state.